diff --git a/.gitmodules b/.gitmodules
index 90e702c..0f542ca 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -10,3 +10,6 @@
 [submodule "hw/super6502_fpga/src/sim/sub/verilog-6502"]
 	path = hw/super6502_fpga/src/sim/sub/verilog-6502
 	url = ../verilog-6502.git
+[submodule "hw/super6502_fpga/src/sub/sd_controller"]
+	path = hw/super6502_fpga/src/sub/sd_controller
+	url = ../sd_controller.git
diff --git a/hw/super6502_fpga/src/sub/sd_controller b/hw/super6502_fpga/src/sub/sd_controller
new file mode 160000
index 0000000..361219f
--- /dev/null
+++ b/hw/super6502_fpga/src/sub/sd_controller
@@ -0,0 +1 @@
+Subproject commit 361219ff1a2b2f2c7dfc6c1dbeb7390c656823af